1. Field of the Invention
The invention pertains to isothiazolyl ureas, particularly 1-(3-methyl-5-isothiazolyl)-3-alkoxy-3-methylureas, such as 1-(3-methyl-5-isothiazolyl)-3-methoxy-3-methylurea, and the method of controlling weeds with these ureas.
2. Description of the Prior Art
The Herbicide Handbook of the Weed Science Society of America, 3rd. Edition (1974), obtainable from the Weed Science Society of America, 425 Illinois Building, 113 N. Neal Street, Champaign, Illinois 61820, shows the following commercial ureas used to control weeds:
3-(4-bromo-3-chlorophenyl)-1-methoxy-3-methylurea, page 93; m-(3,3-dimethylureido)phenyl-tert-butyl carbamate, page 220; 3-[p-(p-chlorophenoxy)phenyl]-1,1-dimethylurea, page 98; 3-(p-chlorophenyl)-1,1-dimethylurea, monotrichloroacetate, page 225; 3-(3,4-dichlorophenyl)-1,1-dimethylurea, page 172; 3-(3,4-dichlorophenyl)-1-methoxy-1-methylurea, page 221; 1,1-dimethyl-3-(.alpha.,.alpha.,.alpha.-trifluoro-m-tolyl)urea, page 194; and 3-(hexahydro-4,7-methanoindan-5-yl)-1,1-dimethylurea, page 280. Also disclosed is the cyclic urea 1-(2-methylcyclohexyl)-3-phenylurea, page 356.
Other ureas giving herbicidal activity are disclosed in U.S. Pat. No. 3,454,591 (1-(3-methyl-5-isothiazolyl)-3,3-dimethylurea), U.S. Pat. No. 3,622,593 (1-(5-isothiazolyl)-3,3-dimethylurea), French Pat. No. 2,132,691 (1-(3-methyl-4-ethoxycarbonyl-5-isothiazolyl)-3-methylurea), Netherlands application No. 6,605,902 (1-(3-methyl-5-isothiazolyl)-3-methylurea), U.S. Pat. No. 3,922,160 (1-(3-methyl-4-cyano-5-isothiazolyl)-3,3-dimethylurea), German Offenlegungsschrift 2,434,922 (1-(3-methyl-4-cyano-5-isothiazolyl)-3-methoxy-3-methylurea), and German Offenlegungsschrift 2,408,234 (1-(3-methyl-4-acetyl-5-isothiazolyl)-3-methoxy-3-methylurea).
U.S. Pat. No. 3,563,985 describes a method for preparing ureas, carbamates, and thiocarbamates having a 3- or 5-isothiazolyl ring attached to one of the nitrogen atoms thereof.